Manhole and inspection cover and frame



March 20, 1951 v. ELKINGTON 5 MANHOLE AND INSPECTION COVER AND FRAME Filed April 2, 1945 2 Sheets-Sheet 1 I6 F/G./ w /2 /l Inventor ltorneys March 20, 1951 v. ELKINGTON 2,545,771

MANHOLE AND INSPECTION COVER AND FRAME Filed April 2, 1945 2 Sheets-Sheet 2 y In uentor y 3 2 4 7% ttorneyS Patented Mar. 20, 1951 MANHOLE AND INSPECTION COVER AND FRAME Vivian Elkington, Watford, England Application April 2, 1945, Serial No. 586,245 In Great Britain May 15, 1944 1 Claim.

This invention relates to manhole and inspection covers and frames, and is concerned particularly with close fitting covers and frames such as are described, for example, in the specification of my prior British Letters Patent Nos. 447,063 and 472,760, and the object of the invention is to provide a means by which such covers can be opened up by a hinging movement while preserving their air and gas tight characteristics.

The invention can be broadly defined as a hinging device, attachable at will to the cover and frame, and consisting of two members, connected by a hinge, one of which members is adapted to be attached to the frame and the other to the cover with the hinge lying above and in axial alignment or parallelism with the top edge of the meeting and abutting faces of the cover and frame.

Means may be provided to limit the extent of the hinging movement.

A convenient method of attachin the members of the hinge structure to the cover and frame will be best understood by reference to the specification of my prior British Letters Patent No. 522,548, which discloses a lifting key, the purpose of which is to break the joint between cover and frame to enable the cover to be removed.

In adapting such a device to the attachable hinge device of the present invention, each of the hinge members i provided with a fixing bolt adapted to make engagement with a part of the cover and frame respectively'so that the members of the hinge device are temporarily locked to the cover and frame respectively. Thus the cover and frame are in effect hinged together when the hinge device is in situ. This involves, of course, providin the frame as well as the cover with means by which the attachment can be made. In the case of small covers a single centrally arranged hing device may be sufiicient but it will be understood that provision may be made for any number of these devices to be applied at different positions .along the joint of the cover and frame, and the arrangement of cover and frame will preferably be such that the hinging devices can be applied to either side of the cover as convenience may dictate.

In order that the invention may be clearly understood and readily carried into practice it is illustrated, by way of example only, by the accompanying drawings, in which:

Figure 1 is a sectional view through a hinge applied to one edge of an inspection cover or manhole, on line I-I of Figure 2;

Figure 2 is a plan view of the hinge with the 2 adjacent parts of the cover and surrounding frame; 7

Figure 3 is a section on line 33 of Figure 2 with the cover raised, and

Figure 4 shows a hinge locking pin.

The marginal frame of the cover I is assumed to consist of hollow or cavity members 2, and the surrounding frame 3 of the cover to contain a cavity 4. In order to enable hinges to be removably fitted thereto in accordance with the present invention, the surrounding members 2 of the cover and of theframe 3 are provided at intervals with elongated holes or slots respectively, which are so disposed as to come opposite to one another when the cover I is fitted into the frame 3. The said holes and slots open respectively into the 'cavities of members 2, and into the cavities l of frame 3.

The removable hinges comprise a pair of plates 5 and B carrying interengaging hinge lugs I bored to receive a common hinge pin 8. The plate 5 is bored to receive a securing bolt 9 and the plate 6 is slotted to receive a securing bolt Ill. The two bolts 9 and I0 comprise threaded shanks carrying nuts II, fitted at one end with a nut retaining head I2, and terminating at the other end in a rectangular or other non-circular head I3 adapted to pass through the holes or slots in cover member 2 and frame 3, and then to be rotated through an angle into positions lying across said holes or slots and therefore held from disengagement therefrom when the nuts I I are tightened down to clamp the hinge plate 5 and 6 to the frame 3 and cover I respectively.

In consequence of the above construction one or more of such hinges can be readily applied to any edge or side of a cover I and frame 3 provided with the necessary holes and slots for bolts 9 and III, which are 50 positioned as to locate the hinge with the axis of its hinge pin lying above the junction line between cover I and surrounding frame 3. Subsequently the hinge can be removed by slackening the nuts II sufficiently to enable the bolts 9 and I!) to be rotated into positions in which their heads I3 can be drawn through the holes and slots in cover member I and frame 3.

The hinge device preferably includes means for holding the cover I in raised position, namely, a pair of end plates or wings I4 formed by webs on the hinge plate 5, and a pair of end plates or wings I5 formed by webs on the hinge plate 6, which are spaced closer together than the end plates I4, so as to come adjacent to the inner surfaces thereof when the cover I is raised. In

these end plates are formed holes l6, which come into register when the cover I is in raised position, as shown in Figure 3, whereupon a locking pin (Figure 4) may be passed through the registering holes. Obviously a series of holes may be provided in wings I4 or I5 to enable the cover to be locked in various raised positions, instead of only in the fully raised position, as shown in Figure 3.

By providing the necessary cavities and holes for the hinge securing bolts 9 and Hi, all round the cover I and surrounding frame 3 it will be possible to hinge the cover alon the most convenient edge, as determined by the surrounding objects and structures.

In the operation of the device the hinge device or devices will be applied to one side and the key for initially breaking the joint to the opposite side. The joint will be broken in the normal way and the cover can then be swung about the hinge device or devices as desired.

After the inspection, or other purpose for which it was necessary to open the cover, has been accomplished, the cover will be replaced and the hinge device or devices and joint breaking devices removed.

It will be understood that in the designing of the covers and frames regard will be had to the angles and curvatures of the meeting faces of the covers and frames to accommodate the arc of movement about the hinge.

Although primarily designed for use with the close fitting covers and frames the subject of my earlier patent above alluded to, it will be apparent that the invention can be applied to covers and frames of other kinds and provides a means by which manhole and inspection covers, in general, can be transformed at will to hinged covers. The invention may also be applied to covers forming a series covering a long trench or duct.

Thus I have by my invention provided manhole and inspection covers which during normal times are not hinged, and thus are without any of the disadvantages consequent on permanent hinging, but can at will be turned into hinged covers.

I claim:

The combination with a manhole frame and cover, each of which is provided with a cavity having a slotted opening thereinto, of a hinge device for connecting the cover to the frame, said hinge being composed of a frame hinge plate and a cover hinge plate pivotally connected thereto, said plates having bolt openings therethrough, an adjustable fastening member for detachably connecting the frame plate of the hinge to the frame and having a head at one end thereof for seating in the recess of the frame when the fastening member is slidably inserted in said frame, said fastening member having an adjustable nut thereon for clamping the frame plate of the hinge in position on the frame, and a retaining member at the end of said fastening member opposite the head above referred to, a second fastening member for detachably connecting the cover plate of the hinge to the cover and having a head at one end receivable in the recess of the cover, and an adjusting nut thereon for clamping the cover plate of the hinge on the cover.

VIVIAN ELKINGTON.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Number Name Date 587,210 Jackson July 27,1897 736,714 Gendron Aug. 18, 1903 1,210,595 Brubaker Jan. 2, 1917 1,589,063 Fondo June 15, 1926 FOREIGN PATENTS Number Country Date 250,522 Italy Oct, 16, 1926 

